FranticFish - 5:36 pm on Jun 24, 2010 (gmt 0)
Investigating link profiles recently I've seen what I think is a nifty spammers trick that involves getting one way links by cheating recip management software that automatically checks for their link on your site.
Here's how I think it works:
Use a dummy site to request a swap.
Give them a url where they expect to find the link.
Check for the IP that requests that url.
Now on your proper site set up a hidden link page cloaked via IP.
Request an exchange again, cloak to that IP.
Bot goes away happy thinking it's reciprocal, you have a one way link.
Works well on old sites that use these directories, have forgotten they even have them, and have authority from being around for ten years plus. Quite a lot of them around, especially in the US.